1. Field of the Invention
The present invention relates to a video image processor and in particular to a special effects generating apparatus which applies video image conversion processing to an input video image.
2. Description of the Prior Art
There has recently become popular special effects generating apparatus which is capable of adding various special effects to an input video signal.
An apparatus which is capable of adding special effects to an input video signal converts the input video signal into digital data, stores the digital data in a memory and processes the digital data in the memory. This conveniently adds special effects an the input video signal.
The present assignee discloses in U.S. Pat. No. 4,965,844 and Japanese Unexamined Patent Publication No. Sho 58-219664 a video image conversion apparatus which is capable of adding special effects to an input video signal.
This video image conversion apparatus displays on the screen a video image which is viewed as if an input video image is applied on a three-dimensional curved surface (for example, a cylindrical surface) by converting a television signal into a digital signal. In order to perform a digital video image processing in real time, the three-dimensional curved surface is approximated as an assembly of pseudo curved surfaces by assuming that the three-dimensional surface comprises a multiplicity of polygonal (for example, triangular, parallelogrammatic, trapezoidal) surfaces and mapping is performed so that the two-dimensional video image is split into each pseudo-curved surface.
There is to be considered as a special effect which is to be added to an input video signal, an effect as if a displayed video image were exploded by diffusing the displayed video image.
However, although various apparatuses which provide special effects have been proposed, no apparatus which provides an explosion effect has been proposed and the development of an apparatus for providing such an explosion effect is desired.
Therefore, it is an object of the present invention to provide a special effects generating apparatus which is capable of providing an input video image with a special effect as if the input video image were exploded by diffusing data of each pixel of the input video image toward the periphery of the screen.